I use grep many time but always forget options. So I wrote this for my future self and may be help someone too!

All the GREP Command Switches You Need to Master in Linux

The grep command is one of the most powerful tools in any developer’s or system admin’s toolbox. It helps you search for patterns, filter files, scan logs, and analyze text — all from the terminal. Here's a full list of useful and practical options you can use with grep every day.

1. Basic Pattern Matching

grep "error" logfile.txt

Searches for lines containing the word error in logfile.txt.

2. Useful GREP Switches with Examples

🔍 -i — Case Insensitive Search

grep -i "error" app.log

Matches "Error", "ERROR", "eRrOr", etc.

📁 -r or --recursive — Search in Folders

grep -r "function" ./src

Recursively search "function" inside all files under ./src.

🔢 -n — Show Line Numbers

grep -n "TODO" main.py

Shows which line contains the match (useful for debugging).

🚫 -v — Invert Match (Exclude)

grep -v "DEBUG" server.log

Show all lines except those that contain DEBUG.

📄 -l — Show File Names Only

grep -l "connect" *.js

📄 -w — Show exact match

grep -w "kamal" users.csv

List only filenames where the  exact match occurs.

👁️ -A / -B / -C — Show Surrounding Context

grep -A 2 -B 1 "error" logs.txt

Shows 2 lines after and 1 line before each "error" match.

🔁 -E — Use Extended Regex

grep -E "warn|error" logs.txt

Matches "warn" OR "error". Very useful for complex patterns.

📈 -c — Count Matches Only

grep -c "user" users.csv

Just show how many lines contain the word "user".

⚡ --color=auto — Highlight Matches

grep --color=auto "main" app.js

Shows your matches in color, useful for spotting results fast.

Bonus: Combine grep with Other Commands

ps aux | grep node

Filter system processes to see only Node.js related entries.

Conclusion

In my experience, learning grep properly has saved me countless hours of debugging, searching code, and even monitoring servers. These options aren’t just for sysadmins — they’re for every developer who lives in the terminal. Bookmark this guide or save a cheat sheet, and next time you're lost in a sea of text, let grep do the heavy lifting.

Got a favorite grep trick? Share it in the comments!